1. Field of the Invention
The present invention relates to pill crushers for use in crushing medicaments in the form of pills or tablets.
2. Description of the Related Art
Medications are commonly provided in the form of pills or tablets, and it is well known that these can be difficult to swallow for various persons. Consequently, various pill crushers have been proposed in the prior art for crushing pills and tablets so as to convert the medications into powder form, which can be more easily ingested by such persons.
For example, U.S. Pat. No. 3,915,393, issued Oct. 20, 1975 to Bill Webb Elkins, discloses an apparatus for crushing medications, such as pills, tablets and the like, which includes a base member having a crushing bowl formed therewith, which is adapted to receive a medication cup containing medicine to be crushed. The apparatus further-includes a crushing arm pivotally mounted on the base member and having a crusher head mounted on the crushing arm. By pivoting the crushing arm relative to the base member, the crusher head can be forced downwardly onto the medication, which is contained between a pair of interengaged cups positioned in the crushing bowl.
In this prior apparatus, the crushing head is fixedly secured to the crushing arm, and the interengaged cups are supported on the base member. Therefore, there is no relative rotational movement between the undersurface of the crushing head, and the upper surface of the base member, on which the cups are supported, during the crushing of the medication. Consequently, it has been found, in practice, that the medications are not sufficiently pulverized by such crushing action.
In U.S. Pat. No. 6,357,679, issued Mar. 19, 2000 to George F. Radke, there is disclosed apparatus for crushing medication having a crushing member which is rotatable relative to an anvil, as medication is crushed between the crushing member and the anvil. More particularly, this prior apparatus has an anvil mounted on a base, and a crusher member mounted in a housing for rotation about a first, horizontal axis relative to the housing. The housing has a cam surface which mates with a follower connected to the base, which produces rotational movement of the housing about a second, vertical rotational axis as the crushing member with its housing are displaced downwardly, toward the anvil, in order to a crush medication provided between interengaged cups between the crusher member and that the anvil.
It is, however, a disadvantage of the apparatus of U.S. Pat. No. 6, 357,679 that the force required for crushing medication must be directed vertically downwardly onto the housing, so that there is no lever action between the crusher member and the anvil. Consequently, this prior art apparatus cannot easily be employed by weak or otherwise disabled persons.
It is, accordingly, an object of the present invention to provide a novel and improved pill crusher which improves the crushing of pills without requiring the application of any significant amount of strength.
According to the present invention, a pill crusher comprises an arm extending over and along an elongate base, with a pivotal connection between the base and one end of the arm. An upwardly open, cylindrical housing on the base has a longitudinal axis perpendicular to the base, and a cylindrical anvil is provided in the cylindrical housing on a compression spring located between the anvil member and the base.
Interengaged guide formations on the cylindrical housing and the anvil member,at opposite sides of the housing, are inclined so as to cause rotational movement of the anvil member relative to the cylindrical housing upon displacement of the anvil member against the action of the spring. A cylindrical pressure member depends from the arm above the cylindrical housing.
When the apparatus according to the present invention is in use, a pill it is inserted into a cup, and another cup is interengaged with the first cup, so that the pill is located between the two cups. The two cups, with the pill between them, are then placed on the anvil member, and the arm is pivoted downwardly to bring the cylindrical pressure member into the uppermost cup. During further downward movement of the pressure member toward the anvil member, the pill is crushed between the pressure member and the anvil member. Furthermore, during this crushing of the pill, the downward movement of the pressure member causes the anvil member to be downwardly displaced relative to the cylindrical housing. This movement of the anvil member relative to the cylindrical housing, through the interengaged formations, causes relative rotational movement of the pressure member and the anvil member. Therefore, the pill it is not only crushed but is, also, simultaneously ground between the two cups.
The combination of the force exerted on the pressure member by the lever action of the arm, with the grinding of the medication caused by the relative rotation of the pressure member and the anvil member, has been found to produce improved pulverization of the medication.
Furthermore, but it has been found that the pulverization of the medication can be still further improved by the provision of serrations on opposed services of the pressure member and the anvil member.